1. Technical Field
The present disclosure relates to a method for upgrading hydrocarbon using C4, C5 and C6 streams.
2. Description of the Related Art
Residue Fluidized catalytic cracking (RFCC) process is a process for producing LPG, gasoline, diesel, naphtha, etc. by fractionating a crude oil, is and then catalytic cracking a heavy residual oil remaining after the fractionation. Heavy residual oil itself do not include a fuel, and so it may be further cracked to produce LPG, gasoline, diesel, etc., which is referred to as a ground oilfield, one of the major oil companies advanced equipment.
Products that can be obtained through the RFCC process may include a wide range of materials, such as LPG, gasoline, diesel, etc., according to their boiling points, but the main target product has been gasoline to date. The yield of gasoline in the current RFCC process is around 50% by weight, and considering MTBE and alkylates produced from C4 product obtained through RFCC process, the gasoline yield may be more than 60% by weight.
However, with a reduced gasoline demand and a development of alternative energy sources for shale gas based gasoline, gasoline prices are falling steadily, and these trends are expected to intensify in the future.
Due to these trends, it is required that the target material in the RFCC process be changed by other materials in place of gasoline, and diesel may practically be considered as a faster alternative.
Typically, in RFCC process, C4 product has been used to produce C8 alkylates by reacting selectively separated iso-C4 paraffins with MeOH to afford MTBE, and then alkylating remaining C4 mixtures. Specifically, in RFCC process, C4 derived MTBE was used as an additive for gasoline, and C8 alkylates were used as a higher grade of gasoline. In other words, C4 product in RFCC process may be thought of as converted into gasoline by the reaction.
However, as described above, due to the increase in the gasoline supply and the reduction in the gasoline demand, the price of gasoline becomes increasingly lower, and so it is expected that these trends will become increasingly more severe. Therefore, considering these trends, the current methods of converting RFCC C4 products into MTBE and C8 alkylates and applying same to gasoline are problematic, and so there exists a need to increase the economic efficiencies by modifying the objects and the methods to those producing other higher valuable compounds.
Generally, C5 and C6 products in RFCC process are also included in the area of gasoline and used as a gasoline, as classified according to their boiling points. But the octane numbers of C5 and C6 products in RFCC process are too low for use as gasoline. Currently, since there is no technique for converting the C5 and C6 products in RFCC process into high value materials, C5 and C6 products in RFCC process are in use as gasoline with lower octane numbers.
Likewise, problems and needs as described above have also occurred to the products from, in addition to the RFCC process, for example, such as naphtha cracking process, heavy oil upgrading process, thermal cracking process, etc.